The present invention relates to a slide-type constant velocity universal joint such as a tripod-type constant velocity universal joint which finds its major use in automotive drive shaft systems.
Constant velocity universal joint of tripod type has been broadly used in drive shaft systems of vehicles and, particularly, drive shaft systems of automobiles of front-engine and front-wheel drive type.
This type of constant velocity universal joint is known for its reduced friction resistance of sliding parts during its operation, as disclosed in, for example, Japanese Post-Examination Patent Publication No. 20810/1968, but is still unsatisfactory in the following points:
Namely, as will be explained in detail later with reference to the drawings, this type of constant velocity universal joint, when used in the drive shaft system of an automobile, causes lateral vibration of the body of the automobile in the frequency region near the resonant frequency of the body, particularly when it operates under a comparatively large accelerating torque with a large joint angle formed between both axes of the shafts thereof. More particularly, the vibration becomes serious when the joint angle exceeds a range of from 3.5 to 4.5 degrees. For this reason, it has been necessary to design the automobile such that the joint angle formed between both shafts of the joint does not exceed 4.0 degrees during its operation. This undesirably limits the degree of freedom in design.
In order to overcome this problem, a tripod type constant velocity universal joint has been proposed in which a needle roller bearing and a pair of guide rings which make spherical surface contact with each other are disposed between each trunnion and a roller mounted thereon, as disclosed, for example, in Japanese Post-Examination Patent Publication Nos. 47413/1981 and 13211/1982 and Japanese Post-Examination Utility Model Publication No. 23864/1984. This tripod type constant velocity universal joint, however, is still unsatisfactory.